Mismatch between myocardial accumulation of 123 I-MIBG and 99m Tc-MIBI and late ventricular potentials in patients after myocardial infarction: Association with the development of ventricular arrhythmias, ,

Background Late ventricular potentials are widely used to predict life-threatening arrhythmias, although the predictive value is low. To improve prediction, we correlated the incidence of ventricular arrhythmias with mismatches in myocardial 99m Tc-methoxyisobutylisonitrile (MIBI)/123 I-metaiodobenzylguanidine (MIBG) accumulation and late ventricular potentials (LP). Methods and Results Fifty patients with old myocardial infarctions were divided into an LP-positive group (n = 19) and an LP-negative group (n = 31). On bull’s-eye single photon emission computed tomographic MIBI and MIBG images, the heart was divided into 9 segments to evaluate the accumulation of the 2 nuclides. There was no difference in total defect score (TDS) for MIBI between the LP-positive and LP-negative groups. However, TDS for MIBG and differences TDS between MIBI and MIBG (ΔTDS) were significantly greater in the LP-positive group. Conclusions The incidence of severe ventricular arrhythmias was greater among patients with an increased ΔTDS in the LP-positive group. Thus the combination of these two methods may improve the prediction of ventricular arrhythmias after myocardial infarction. (Am Heart J 1998;136:859-67.)